Coating apparatus



July 14, 1942. J. F. EARP COATING APPARATUS Filed Aug. 15, 1940 5 Sheets-Sheet 1 July 14, 1942. J. F. EARP 2,289,763

COATING APIZ'ARATUS Filed Aug. 15, 1940 5 SheetS-Shet 5 J. F. EARP I COATING APPARATUS July 14, 1942.

5 Sheets-sheaf 4 Fild Aug. 15, 1940 July 14, 1942. J. F. EARP COATING APPARATUS Filed Aug. 15', 1940 5 Sheets-Sheet 5 Patented July 14, 1942 UNITED STATES PATENT oFFica coarmc arranaros James F. u Detroit, Mich, mum: to The American Ohio,

Paper Bottle Company, Toledo, a corporation of Ohio,

Application August 15, 1940, Serial No. 352,794 I 16 Claims.

This invention relates to mechanismsfor applying coatings to articles of various kinds but more particularly to mechanisms for coating partially completed paper containers. Paper bottles and containers are customarily .coated interiorly and exteriorly with a protecting sub-,

ing of milk is described and claimed in Patent' 2,047,891, issued July 14, 1936, in the name of Henry '1; Scott. That container is tubular, rectangular in cross-section, and is of a type which may be readily fabricated, charged and sealed on a complete automatic machine designed for that "purpose. The paper used in the fabrication of the container, while of best quality, must nevertheless becoated with a substance which will prevent contact of-the fibers of the paper wall with its liquid contents, whether such contents be milk, oil, or other liquid, in order that the wall of the container may keep its original strength and the container its shape and durability.

In Patent 2,133,214, issued October 11, 1938, to Henry T. Scott is disclosed'and claimed a coating apparatus primarily designed for use in applyinga coating to all surfaces, bothexterior and interior, of a paper container of the type disclosed in Patent 2,047,891, just prior to the charging, closing, and sealing of the container, the apparatus including means for successively introducing containers into the carriers of an endless series of container carriers moving along a closed path, a portion of which path lies below the level of the surface of a bath of coating material, and means forsuccessively removing containers. from the carrier series as they reach a predetermined point, after having been coated. Each successive carrier after having received a container to be coated moves downwardly toward and into the bath of coating material in liquid form, then passes through the bath in such manner that all surfaces of the container are exposed to the liquid of the bath in a desired manner and thereafter removed from the bath bottom I end foremost and drained, each container after bein drained being elected from the coating apparatus by an ejector device and passing onto further mechanism for chilling and solidifying the coating, charging the container with liquid and closing and sealing the same. I

The present invention comprises animprovement upon the coating apparatus just above briefly described and its primary p pose i to simplify, speed up, and render more effective in operation the previously patented apparatus. It

is likewise intended that the improved apparatus shall occupy less space for a given capacity than the earlier one, and that a simpler means for "liquifying solid coating material, and supplying it to the bath, be provided. Other features of improvement are incorporated into the coating apparatu which comprises the subject matter of the present invention, the number of operating parts being, for example; considerably reduced and thus the cost of construction and maintenance being minimized.

By way of example one form of the'invention is ,illustrated in the accompanying drawings in hich:

Figure 1 is a side elevation of the coating apparatus and the associated means for liquifying solid coating material:

Figure 2 is a section on line 2-2 of Figure 1 certain parts of adjacent mechanisms being also included;

Figure 3 is a section on line 3-3 of Figure 2;

Figure 4 is a section on line H of Figure 3;

Figure 5 is a partiallongitudinal section, taken on the line 5-5 of Figure 6, through one of the carrier elements;

Figure 6 is a section on line 6-6 of Figure 5;

Figure 7 is a section on line 1-1 of Figure 1, portion of the air nozzle there illustrated being partly broken away to show more clearly an interior air passage;

Figure 8 is a front elevation,'partially broken away, of the coating material liquifying device shown in side elevation in Figure l;

Figure 9 is a section on line 9-9 of Figure 8;

Figure 10 is a section on line llllil of Figure V 8; and

Figure 11 is a section on line IiI--,ll of Figure 8.

The coating apparatus selected for illustration includes a container or kettle for a bath of molten coating material, a series of carriers each designed and intended to receive an article to be coated, to move the article into and through the bath, and to then lift the article above the surface of the bath to a position adjacent a discharging mechanism by means of whichit is removed from the carrier. Heretofore mechanical means has been employed to placea container to be charged within one of the carriers, and a second mechanical device utilized to effect removal of the coated container from the carrier. The

- which is carried out 2 I present invention contemplates the elimination of these mechanical container charging and discharging devices and the substitution therefor of simple and' inexpensive pneumatic means. Thus, the container to be coated is actually blown by an air blast "into the container carrier or container receptacle and, after having been coated,

is blown by another air blast out of the carrier and into a mechanism especially designed to re ceive it and to effect its transfer to some further mechanism for acting upon the same.

The carrier elements or receptacles are indicated in the drawings by the numerals l0, l and from an inspection of Figures 2 and 3 it will be observed that these carriers are elongated tubular members, rectangular in cross section, and open at both ends, the inner walls being provided with ribs II which function to prevent the outer surface of any container placed within the carrier from having contact with the inner wall surface of the carrier over any substantial area, thus insuring that all outside surfaces of the articles to be coated may be reached by the coating materiaf. There are a number of carriers l0 and each is provided with a bracket l2 by means of which it is mounted on a chain l3, the chain l3 passing aroundsprockets II and Ila mounted for rotation about parallel axes, respectively, the arrangement being such that, when the chain is moved in the direction of the arrow A (Figure 3) the carriers It will pass downwardly in succession, pass under the surface of the bath of coating material such as molten paraflin which is indicated at P, through the bath, and thence upwardly to a point of discharge. carriers In together with the means upon which these carriers are mounted are housed within a casing the lower part I! of which is in the nature of a steam kettle and the upper part I6 of which maybe of relatively light sheet metal, this upper portion l functioning retain heat and vapor andto prevent contamination of the coating substance.

As shown, the several containers II are angularly disposed with respect to the horizontal when moving vertically and purpose of insuring that, when the apparatus is being used to coat containers of the tubular type, with one closed end, each successive container is introduced into the bath bottom end foremost. The mechanism is so designed that the container is then moved in such manner through the oath that all wall surfaces thereof are e p t0 the liquid in the most eflective manne and is removed from the bath bottom end foremost; all for purposes set forth at greater length in Patent 2,133,214, previously referred to and likewise in Patent 2,133,213, in which the method of coating by the present machine is fully described and claimed.

Formed in the opposite parallel walls of casing it are apertures 23 and 2| for the introduction into'the casing of containers to be coated, and the discharge from the casing of containers which have been coated, respectively, the inlet opening 20 being approximately horizontally opposite the outlet opening 2|. The openings are so located that, when the right-hand open end (Figure 2) of a carrier II is disposed in with the inlet opening 2! in the casing, the left-hand open end of the carrier ll immediately above is in register with the discharge opening 2|, the arrangement thus being such that both charging and discharging operations may be simultaneously effected, a carrier The series of principally as a means tor this is primarily for thelocated at position immediately above it.

' application just above referred '26 in Figure 2, all

1 registering carrier after the carrier Illa (Figure 2) being so positioned that it will receive a container introduced through opening 20 and -the carrier next immediately above and occupying the position Illb, being aligned with opening 2|.

The carrier actuating means is intermittently operated by a suitable mechanism so that, for charging and discharging purposes, carriers are momentarily halted in positions such as Ma and lllb (Figure 2), to permit a container to be coated to be placed in one carrier and a container which has been coated to be discharged from the carrier Means for effecting the intermittent movement of the carriers may be of any desired type. In Figure 2 the sprocket I4 is shown to be fixed upon a shaft 22 supported in bearings 23 and extending outwardly through an aperture formed in the casing wall, the shaft having a gear 22a fixed on its outer end the teeth of which mesh with those of a gear 24 fixed upon a shaft 25 which may conveniently be the supporting shaft of the mandrel carrying spider of a container squaring-out and bottom closing mechanism of the type disclosed and claimed in copending application, Serial No. 340,358, filed June 13, 1940, Charles Z. Monroe.

The squaring out and bottom closing mechanism which comprises the subject matter of the to includes a plurality of mandrels, of which one is indicated at of these mandrels being disposed radially of shaft 25 and being adapted to be successively brought into alignment with the charging opening 20 of the coating apparatus casing and into alignment with that container carrier ||l which happens to have its receiving aperture in register with opening 20 at that time. Pneumatic means, moreparticularly described in the copending application mentioned, may effect the transfer of a container from mandrel 26, the position of a container, the bottom of which has been closed, mounted on this mandrel, being indicated in chain lines, to the aligned carrier l0 and in the preferred form of pneumatic means employed compressed air is passed from a suitable source through a conduit 30 to a valve 3| and, when the valve is opened, is allowed to flow through duct 32 into compressed air ducts formed in mandrel 26 so that jets of compressed air will issue from the free end of the mandrel and against the bottom of the container mounted thereon, thus blowing the container into the lil, bottom end foremost.

After having been coated and drained, and in which the container is held reaches the position lob, (Figure 2) further pneumatic means becomes active to blow the container from the carrier and this means includes the nozzle member 35 attached to the casin wall and having a downwardly and inwardly inclined discharge port 36 whereby a jet of air may be directed axially through a carrier in position lllb to strike the inside surface of the bottom of a container lying within such carrier. The

nozzle device 35 may be conveniently supplied with air under pressure through a duct diagrammatically illustrated at 31"Ieading to valve 3|, so that when valve 3| is opened, both the container charging and the container discharging mechanisms are called into action, both operations occurring simultaneously. The container 33, with its bottom chain lines on the mandrel 26 is in position to be discharged into the coating apparatus, a container within one of the carriers I0 is indicated end closed, indicated in opening of such carrier.

at at, and a container whichjhas just been ejected from the coating apparatus is indicated in chain lines at 38c. This container 38c is shown to be retained-within an uprighting element In pivotally mounted at 4| and movable from the'full line position in which it is shown in Figure 2 to the position in which it is shown in dotted lines in that figure, for the purpose of erecting the container and placing itin position to be engaged by a pusher member 42 of a container cooling mechanism more fully described in my copending application Serial No. 359,440, filed October '2, 1940.

During the vtime that a container is retained within a carrier member I and is moving downwardly toward or into the molten bath of coating material, it must be positively prevented from floating upwardly .out of the upper or charging Naturally, when the bottom of the empty container comes into contact with the coating liquid, the container will tend to float and, unless confined, its upper end will be projected against the inner wall of the housing and will be injured. Latching means is associated with each carrier member, therefore. for preventing the escape of the container within it under such circumstances, this latching means being most clearly shown in Figures 3,

Sand 6. Thus upon the outer wall of each carrier, at one comer and adjacent that end opening through which containers are charged there is formed a bracket 45 upon which bracket is pivotally mounted a latch member or gate 5. Gate 46 comprises an elongated element which is normally retained in a slot III of the carrier by means of a spring 41 one end of which is connected to the free end of the gate and one end to a lug 48 integral with the carrier Ill. The gate or latch includes an actuating arm 49 having a rounded edge 49' which is adaptedto contact with the cylindrical surface of a revolubly mounted disc or roller 50 supported in bearings upon the casing l5.

The arrangement is such that, as each successive carrier Ill reachesthe position of that carrier which is indicated at Illa in Figures 2 and 3, or just before this position is reached, the arm 49 of the associated latch. or gate member strikes the stationary roller 50 so that the, gate is moved to the position indicated in Figure 3 against the tension of the associated spring. When this movement occurs, the two projections 46' of the gate are withdrawn from the interior of the carrier, which carrier is then wholly unobstructed and may receive a container blown 0E of the mandrel 25. Shortly after, the motion of the carrier is resumed, the arm 49 of the gate member disengages the roller 50 and the gate closes. the projections 46' occupying the positions in which they are shown in Figures 5 and 6, in advance of the forward edge of the container.

which container is shown in full lines in Figure 5 and in chain lines in Figure 6. thus preventing escape of the container upwardly when its bottom strikes the bath P. Escape of the containor from the opposite end of its carrier, of course. is not prevented by the gate member 46' but there is little tendency for this to happen and, should a container tend to slide from the discharge end of a carrier as position llib is an proached, it will be prevented from doing so by contact with the inner surface of the side wall of casing it, which is immediately adjacent.

The lower sprocket I la previously referred to is mounted for rotation upon a short hollow shaft ture formed in screws are indicated at 63 respectively, each screw extending downwardly through an apera horizontal flange of bracket and being provided with nuts which permit adjustment and hold it in any desired position of adjustment. The lower ends of the adjusting screws 53 bear against the bracket members 54 terial inclusive. chamber generally indicated at "13, having double and it is by means of screws 63 that the proper tension may be maintained in the endless chain i3 since ,the sprocket Ha may be moved downwardly by the action of the screws, whenever necessary, to tension the chain and take up wear, the telescopic connection including rod' 51 and boss 58 permitting downward movement of-the lower sprocket supporting shaft. The splined connection between rod 51 and boss 58 ensures that the axes of the lower and upper sprockets vshall remain in parallelism at all times.

Projecting through an aperture formed in a side wall of the lower or kettle portion Ma of the casing is a steam temperature control bulb E6 the inner end of this bulb lying within the interior of the sprocket supporting shaft '52. Projecting inwardly through an aligned the lower portion of the casing is a paraiiin temperature gauge bulb 61, both bulbs 66 and El being positioned as shown so as to be'exposed to the action of the molten coating material at a point where temperature fluctuation due to flow of the molten material is least likely to occur, whereby the automatic means for supplying the steam to the kettle at the temperature and in the quantity desired may be most accurately regulated. Likewise the means for indicating the temperature of the bath of molten material will function most reliably.

As shown in Figure 2, the lower wall of the kettle portion I5 of the casing is provided with tortuous passages for the reception of steam and conduits for bringing steam from a suitable source and introducing it into these cavities are indicated at 10 and I I, a steam return and drainage line being indicated at 12. Bysuitable control valves, not illustrated, the fiow of steam may besoregulated that the temperature of the molten coatingmaterial may be maintained at the desired point in an entirely automatic manner. Naturally a small amount of coating mapasses from the apparatus with each container which is immersed and withdrawn and the bath must be replenished from time to time.

The replenishment of the bath is effected by means indicated most clearly in Figures 8 to 11 This means comprises the melting top and bottom walls I4 and 15, double side walls 15 and 11, and a double walled door to the bottom wall 15 at 19. The hollow walls of the chamber may be filled with insulating material to prevent the escape of heat. The back of the heating chamber may comprise a single plate which may rest against a supporting frame member such as indicated at 8| and be secured thereto by brackets 82. v The top and bot tom, as well as the door 18 of the heated cham- 3 52 the ends of which are supported in bearings 58 preferablyformed as integral portions of theto the lower end of aaperture in 18 hinged position,

; of the coating bath may be ascertained with, means associated 4 ber,- are inclined, as shown, and likewise the steam heated material melting member II is disposed at an angle to the vertical, as indicated in Figure 10, so that flat blocks of material such as solid paraflin, which blocks are indicated at ll,

being supported upon a sh melting plate 88. The shelf 85 is perforated as at it to permit melted paramn to pass downwardly, through the screening member I, to the bottom of the chamber from where it through an inclined conduit 8! downwardly toward the coating apparatus, to be discharged into the bath.

The melting plate 83 is maintained in heated condition by steam which is passed through its hollow interior, the plate comprising parallel walls the margins of which are welded to the spacing and sealing strips 90, a baifle strip ii being likewise interposed between these walls. Steam is led to the melting member from a main 92 through a connection such as shown in Ii, which permits swinging motion of plate 03 about a horizontal axis, the plate being supported at its other upper corner upon a hinge pin 84.

. To the inner face of the melting member 83, at

its upper corner, is welded the hollow block 95 and threaded into an aperture in the end of the block is a short tube 96 upon the outer end of which is threaded a sleeve 91 which rather closely fits within a cylinder 8| supported in the side time is free to revolve in this cylinder.- Sleeve 1 also receives with a close fit the reduced end of the stationary steam conduit 99, which is connected to main 9!, so that it may be said that steam is supplied to the melting member I! through a hinge. This permits an operator to swing the member 83 upwardly about an axis adjacent its upper edge to facilitate cleaning of the compartment, the drain pipe lllil at its lower edge swinging with this member.

The paramn or other bath may be drained from the kettle l5, whenever desired, through the valve controlled drain conduit 88', thus emptying the kettle and permitting it to be cleaned. The level by means of the liquid level 93.

It will be appreciated that the novel coating apparatus may be modified, in both the design and arrangement of its component elements,-in adapting the invention to the coating of articles of various kinds, without relinquishing its benefits. Such minor variations are within its scope.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In an apparatus for coating containers or the like, in combination, an endless chain or belt, guidemeans therefor whereby the chain is supported for movement longitudinally in a closed path, a plurality of open-ended container carriers mounted on the chain for movement therewith each. carrier and normally closing one end thereof to prevent emergence of acontainer therefrom, and stationary means for successively actuating said carrier closing means as the carriers pass a predetermined point to permit discharge of containers therefrom.

2. In an apparatus .for coating containers or the like, in combination, an endless chain or belt, guide means therefor whereby the chain is supported for movement longitudinally in a closed path, a plurality of open-ended container carriers mounted on the chain for movement therewith, a member movably mounted on each carrier and normally closing one end thereof, and a stationary device for successively actuating said members as they pass a predetermined point to effect opening of the carriers successively to permit successive discharge of containers.

3. In a coating apparatus, a series of article carriers each inclined to the horizontal and having a chamber for the reception of an article to be coated, said chamber having an opening in its upper end through which an uncoated article may be introduced and an opening at its lower end through which such article may be' discharged, means for moving said carriers along an endless path, a gate device normally closing the discharge opening at the lower end of said chamber, and stationary means for opening said gate device at a predetermined point in the travel of each carrier to permit discharge of its contents. a

4. In a coating apparatus, in combination, a series of article carriers each having a chamber forthe reception of an article to be coated and an opening through which such article may be discharged, means for moving said carriers alon an endless path, a device movably supported on each carrier and normally closing the discharge opening thereof, and means positioned adjacent the path of movement of the carriers for successively actuating said devices as the carriers upon which they are mounted pass a predetermined point, to permit successive discharge of articles at that point.

5. The combination set forth in claim 4 in which each such device comprises a member pivotally mounted on the associated carrier and a spring normally holding said member in carrier closing position.

6. The combination set forth in claim 4 in which each such device includes a member pivotally mounted onthe associated carrier and having an operating arm, the said operating arms successively contacting the means positioned adjacent the path of movement of the carriers whereby each member is moved to uncover the discharge opening of the carrier upon which it is mounted as said carrier reaches a predetermined position.

7. In a coating apparatus, in combination, a plurality of carrier receptacles each having a discharge opening and a member pivotally supported thereon which normally closes said opening, means for moving said carriers along a predetermined path, and a member mounted for revolution about a fixed axis adjacent said path for successively engaging and actuating said pivoted members as they pass and thus releasing articles within the associated receptacles.

8. The combination set forth in claim '7 in series of carrier receptacles each having spaced openings through which articles may be introduced and discharged, respectively, means for moving said receptacles in a closed path, and receptacle loading and unloading mechanism positioned adjacent said path, said mechanism including pneumatic means for simultaneously loading one receptacle and unloading an adjacent receptacle.

10. In a coating apparatus, in combination,

ceptacle loading and unloading mechanism-pcsition'ed adjacent said path, said mechanism including pneumatic means for blowing an article into a carrier receptacle, and a second means for subsequently removing said article from said carrier receptacle.

11. In a coating-apparatus, in combination, a series of carrier receptacles each having spaced openings through which articles may be introduced and discharged, respectively, means for moving said receptacles in a closed ,path, and receptacle loading and unloading mechanism positioned adjacent said path, said mechanism including means for directing blasts of air into successive receptacles to eflect unloading of each such receptacle when it reaches a predetermined point.

12. In a coating apparatus, in combination, a series ot-carrier receptacles each having spaced openings through which articles may be introduced and discharged, respectively, meansior moving said receptacles in a'closed path, and receptacle loading and unloading mechanism po-' sitioned adjacent said path, said mechanism including pneumatic means for blowing an article casing having ports for the introduction and discharge of'artioles, an article carrier within the casing and having ports for the introduction and discharge of an article to be coated, and mechanism for bringing the article introduction port oi the carrier into register with the article introduction port of the casing and thereafter bringing the article discharge port of the carrier into register with the article discharge port of the casing.

. 14. In a coating apparatus, in combination; a

receptacle for a bath of molten material, mechanism including an endless chain, sprockets over which the chain passes, and article carriers mounted on the chain, for submerging articles in the bath and withdrawing them therefrom,

one chain supporting sprocket being carried upon a hollow shaft supported below the level of the into a carrier receptacle, and stationary means for preventing passage of such article through the discharge opening of said receptacle, until said receptacle reaches a predetermined point of discharge. i

13. In a coating apparatus, in combination, a casing the lower portion of which is adapted to retain a bath oi. liquid coating material, said 40 V bulb positioned within the out of contact therewith.

-receptacle for a bath rial, means for introducing articles to be coated ing against an inclined heated bath surface, and means for automatically maintaining the temperature of the bath constant, said means including a temperature indicating said hollow shaft but 15. In a coating apparatus, in combination, a

of molten coating mateinto said bath and withdrawing them therefrom, and means for melting solid coating material and leading the molten material to the bath, said means including a device for supporting a block of such solid material with a major surface restplate, for the purpose set iorth.

.16. The combination set forth in claim 15 in which the. said plate is disposed in a closed chamber and is supported for swinging movement so as to be displaceable to permit access to all interior surfaces or the chamber.

JAMES F. EARP. 

